PHILADELPHIA — Dean Berry was the last kid added to the AAU team, a late substitute when another player on the New York squad got sick before a big tournament in Washington. He had never played in an event like this — a showcase that included top college recruits and future NBA lottery picks — so it was easy to understand why Berry was a bit unsettled as he boarded the double-decker bus taking players across town during a break in the action. But before Berry joined his teammates on the second level, a player from another team stopped him. It was Allen Iverson, the 15-year-old dynamo who stuck…
